Illuminating genetic interactions that affect lipid content in adipocytes

项目摘要

Project Abstract Obesity and associated metabolic disorders are a major health care crisis that affect millions of people worldwide and have no long-term treatment. Most of our current knowledge on how cells regulate their metabolism has been obtained using single gene-driven hypothesis. However, obesity like many other diseases is a polygenic disorder, in which multiple genes interact, contributing to phenotype, which makes it impossible to establish the causative allele. If we are to make any headway towards curing obesity and metabolic diseases during this century, we need bold, creative ideas to tackle cellular pathways as oppose to individual genes that take advantage of cutting-edge high-throughput approaches. As of 2016, over 1.9 billion adults worldwide were estimated to be overweight and 650 million adults to be obese. Obesity is classically characterized by pathological development and differentiation of adipose tissue, which is a key energy storage organ in the body. Adipose tissue stores energy in lipid droplets- until recently unappreciated cellular organelles with complex and dynamic functions. Lipid droplets can drastically change in size as a response to changed calorie intake or metabolism. Since currently FDA-approved anti-obesity drugs act on appetite or metabolism regulation and not on adipose tissue lipids directly, we need to identify pathways responsible for lipid droplet biogenesis and breakdown to improve current therapeutics. Surprisingly, very little is known about the pathways that affect lipid droplets in humans. I will use a CRISPR system to establish a novel high-throughput high-content screening platform in differentiated adipocytes. Since most lipid modifying genes have been discovered in non-mammalian model systems such as C. elegans, Drosophila and S. cerevisiae using siRNA approaches, I aim to develop a novel superior CRISPR screening platform in mammalian system. I will take advantage of inducible CRISPRi mouse our lab has developed to perform a single and dual genetic perturbation screen in primary adipocytes. Thus, my proposed research strategy will illuminate not only new genes but importantly genetic interactions and pathways responsible for formation and breakdown of lipid droplets and provide new targets for anti-obesity therapy.